Thatcher refused to back stronger sanctions on South Africa over apartheid at a Commonwealth conference in 1987.

An Irish diplomat based in London send a confidential message to the Irish PM’s office saying: “There is a wide view too that the Queen is in a rage with Mrs Thatcher over her handling of the sanctions (the Queen, it is said, sees the insensitivity as further damaging ‘her’ Commonwealth at a sensitive time).”

Gerry Adams was rumoured to have been involved in setting up an ambush of an IRA gang by the SAS

Adams was rumoured to have set up an ambush of a notorious IRA gang by the SAS as they tried to blow up a police station in May 1987, according to the files.

Eight members of the Provisional’s East Tyrone Brigade were shot dead after they loaded a 200lb bomb onto a stolen digger and smashed through the gates of the RUC barracks in Loughgall, Co Armagh. British Army special forces were lying in wait and killed them all, along with innocent bystander Anthony Hughes.

The rumour about Mr Adams was passed on to Ireland’s Department of Foreign Affairs by respected cleric Fr Denis Faul about three months after the Loughgall operation.

The priest, who had been at school in St Patrick’s Academy, Dungannon with Padraig McKearney, one of the IRA gang, said the theory doing the rounds was that “the IRA team were set up by Gerry Adams himself”.

In response to the reported remarks in the Government file, a Sinn Fein spokesman said: “These claims are utter nonsense.”

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Gerry Adams was rumoured to be involved in setting up an ambush of an IRA gang by the SAS

Margaret Thatcher’s ministers asked for chauffeur-driven Jaguars rather than Rovers

A number of ministers asked to have Jaguars rather than the usual Rovers.

Under Cabinet rules, most secretaries of state were meant to have Rover 827s. The exceptions were then Defence, Foreign Office and Northern Ireland secretaries, who were given armoured Jaguars for their own security.

The Birmingham Six accused the Irish government of abandoning them

The Birmingham Six, who were wrongfully convicted over IRA bombings in the city, accused accused successive Irish governments of abandoning them in their fight for freedom.

One of them, Paddy Hill, said they had been offered nothing but false hope and false promises in a handwritten letter from his cell in HMP Gartree on September 10 1987.

At the time of the letter Mr Hill had been in jail while four different taoisigh (Irish prime ministers) took office – Liam Cosgrave, Jack Lynch, Garret Fitzgerald and Charles Haughey.

He said governments had done little or nothing to support him and the five others.

The Birmingham Six – Hill, Hugh Callaghan, Gerard Hunter, Richard McIlkenny, William Power and John Walker – were wrongly jailed for life in 1975 in England for the IRA bombings which killed 21 people. After protracted campaigns their convictions were eventually quashed in the appeal court.

Margaret Thatcher and John Major clashed over the economy

Thatcher tore into John Major over his handling of the economy, weeks after backing him to succeed her as prime minister, showing how quickly the relationship soured.

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Margaret Thatcher and John Major clashed over the economy

On Boxing Day 1990, Mr Major wrote to her inviting her to a face-to-face meeting in an attempt to clear the air. It was an encounter he clearly approached with some trepidation, writing anxiously: “I am a little concerned at some of the press comment on a ‘new style’ as this suggests new policies and I don’t wish to change the drift of policy.”

Thatcher wasted no time in making her concerns known, warning that “excessively high” interest rates risked pushing the economy into recession.

She even compared the position to Winston Churchill’s calamitous decision as chancellor in 1925 to return Britain to the gold standard – a move that led to deflation, mass unemployment and the General Strike.

“Mrs Thatcher said conditions on the economy were very tough indeed,” the official minute of the meeting noted. “She believed that there was a danger of repeating Winston Churchill’s historic error.”

She was particularly incensed by his decision to scrap the “poll tax” – her flagship local government reform – even though its deep unpopularity had been a key factor in her downfall.

Margaret Thatcher refused to share her Concorde with a panda

When Washington’s Smithsonian Institution asked to borrow Chia Chia the Panda in 1981, the president of the London Zoological Society, Lord Zuckerman, suggested that she could perhaps share the PM’s flight.

But when Cabinet secretary Sir Robert Armstrong, suggested this, Thatcher’s private secretary responded that she would not be offering Chia Chia a lift.

He wrote: “She has commented that she is not taking a panda with her - ‘Pandas and politicians are not happy omens!”’

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The Queen apparently clashed with Thatcher over South Africa

However, around 100 of the 490 files due to be released were kept back.

The topics of papers we DIDN’T see included...

Britain’s European policy in the early 1990s, including the creation of the Euro and Maastricht Treaty negotiations

Devolution

A file related to the Lockerbie bombing, marked “Lockerbie bombing: Pan Am air crash part 3a”

The marriages of the Prince of Wales and the Duke of York

The Scott arms-to-Iraq inquiry and the basing of US cruise missiles in the UK

Northern Ireland, including regarding British intelligence officer Colin Wallace, as well as the Kincora Boys Home, where young boys were abused by a police informant.

The Bloch Affair – a KGB plot against the CIA

A Cabinet spokesperson said: “We have to ensure all files are properly reviewed and prepared before they are transferred, so that they do not harm national security or our relations with other countries or disclose the sensitive personal data of living individuals.”